A fluid actuator is known, for example, from DE 60 2006 001 040 T2.
In order to control the flow detachment on a wing or a wing flap, the pulsed ejection of pressurized air was found to be more efficient in terms of aerodynamics than, for instance, continuous ejection, since it is possible to make use of instabilities in the flow. This may be learned, e.g., from “On flow separation and its control” by Nishiri, B. and Wygnanski, I. in ECCOMAS; 1996. In the NASA study “Study of the Application of Separation Control by Unsteady Excitation to Civil Transport Aircraft” by J. D. McLean et al. of June 1999 and in the study “Designing Actuators for Active Separation Control Experiments on High-Lift Configurations” by Ralf Petz and Wofgang Nitsche, Berlin University of Technology, the possibility of pulsed ejection of air on the outside of an aerodynamic wing is described.
From the general prior art it is known to use mechanical valves which admit or prevent through flow by periodically opening and closing a flow channel in order to generate a pulsed flow of air. In order to be able to switch high frequencies for the pulsed ejection with the aid of such valves, the cross-sections of flow of the outlet lines must be kept very small, thus engendering high aerodynamic losses. The total pressure losses then amount to more than 90%. In addition, mechanically movable components limit the service life and failure safety of the valves. Usually, fast-switching valves are actuated via solenoids which are characterized by a high intake of electric power, are accompanied by strong electromagnetic fields, and as a general rule necessitate complex control electronics. It is a further drawback of these solutions—since valves provided in this context are only produced in large series—that matching to the particular application in regard of structural size and performance data is, as a general rule, not possible in a meaningful way.